Turkey has transferred two British journalists and their translator charged with terrorism from the Kurdish region to a prison more than 500 kilometers away, angering their news agency.

Correspondent Jake Hanrahan and cameraman Philip Pendlebury work for the U.S.-based Vice News channel. Police arrested them last week as they taped fighting between Turkish soldiers and Kurdish militants, charging them with not having proper media credentials.

They were later charged with helping Islamic State. The reasons for the terrorism charges were unclear.

They were moved Wednesday from the city of Diyarbakir to a prison in Adana.

Turkish authorities said there are more English speakers in Adana. But Vice News said the move took the journalists away from their legal team.

"This move appears to be a blatant obstruction of the fair legal process that Turkey has repeatedly pledged to uphold," said Vice News European news chief Kevin Sutcliffe. "We call on the Turkish government to throw out these ridiculous charges and immediately release our colleagues."

The news team had been reporting as government forces beef up their campaign against militants from the outlawed Kurdistan Workers' Party, which has been fighting a guerrilla war for Kurdish autonomy in southern Turkey.